Answer:
the ratio of the heat rejected to the cold reservoir for the improved engine to that for the original engine is 0.68
Explanation:
Given information
initial efficiency, η
= 0.28
final efficiency, η
= 0.51
ratio of the heat rejected = (1 - η)/(1 - η)
= (1 - 0.51)/(1 - 0.28)
= 0.68
It is fairly easy to build an electromagnet. All you need to do is wrap some insulated copper wire around an iron core. If you attach a battery to the wire, an electric current will begin to flow and the iron core will become magnetized. When the battery is disconnected, the iron core will lose its magnetism. Follow these steps.
Step 1 - Gather the Materials
One iron nail fifteen centimeters (6 in) long
Three meters (10 ft) of 22 gauge insulated, stranded copper wire
One or more D-cell batteries
Step 2 - Remove some Insulation
Step 3 - Wrap the Wire Around the Nail
Step 4 - Connect the Battery
Neither energy nor matter can enter and exit an isolated system.
Explanation:
There are three types of systems which refers to universe. They are
1. Open System : In an open system, both energy and matter have external interactions. Example:- boiling water in an open pan.
2. Closed system : In a closed system, only energy has interaction with surroundings. Example:- boiling water with a lid on the pan.
3. Isolated system : In an isolated system, neither energy-nor matter has external interactions with surroundings. Example : a thermos flask does not exchange energy and matter.
Hence, the correct option is (a) " neither energy nor matter ".
Answer:
The three types of impact that occur are those involving the vehicle, the body of the vehicle occupant, and the organs within the body of the occupant.
